Vehicle seat assembly with impact energy management

ABSTRACT

A vehicle seat assembly is provided with a seat back frame. A bracket is provided with a substrate welded to the seat back frame. Two pairs of sidewalls extend from the substrate and are tapered with an enlarged region at an upper distal end. A pair of support plates are each supported by one of the two pairs of sidewalls and spaced apart from the substrate to provide a mounting surface. A pair of spaced apart tubes are each welded to the bracket mounting surface of one of the pair of support plates. A pair of head restraint posts are each received in one of the pair of tubes. A head restraint is supported upon the pair of head restraint posts, so that upon a rear vehicle impact, the bracket deforms as the pair of head restraint posts are translated toward the seat back frame.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims foreign priority benefits under 35 U.S.C. §119(a)-(d) to DE 10 2019 220 261.6, Filed Dec. 19, 2019, the disclosureof which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

Various embodiments relate to vehicle seat assemblies including a headrestraint extending from a seat back to support the back and head of anoccupant during travel and during a rear impact condition.

BACKGROUND

Vehicle seat assemblies often include a head restraint extending from aseat back to support the back and head of an occupant during travel andduring a rear impact condition.

SUMMARY

According to at least one embodiment, a vehicle seat assembly isprovided with a seat back frame adapted to be mounted to a vehicleinterior. A bracket is mounted to the seat back frame. At least one headrestraint post is mounted to the bracket and spaced apart from the seatback frame so that upon a rear vehicle impact, the bracket deforms asthe at least one head restraint post is translated toward the seat backframe.

According to a further embodiment, the bracket is further provided witha substrate. A projection extends from the substrate. A mounting surfaceis provided on the projection to mount the at least one head restraintpost.

According to an even further embodiment, the projection is tapered withan enlarged region at an upper distal end relative to a lower proximalend.

According to another even further embodiment, the projection is furtherprovided with a pair of sidewalls extending from the substrate.

According to an even further embodiment, the projection is furtherprovided with a support plate supported by the pair of sidewalls andspaced apart from the substrate to provide the mounting surface.

According to an even further embodiment, the support plate is notparallel with the substrate.

According to an even further embodiment, the support plate is orientedat an angle relative to the substrate.

According to an even further embodiment, the angle faces an uprightdirection.

According to another further embodiment, the bracket is formed from asheet of material.

According to an even further embodiment, the bracket is formed fromsheet steel.

According to another further embodiment, at least one tube is mounted tothe bracket and sized to receive the at least one head restraint post.

According to an even further embodiment, the bracket is welded to theseat back frame.

According to an even further embodiment, the at least one tube is weldedto the bracket.

According to another further embodiment, a head restraint supported uponthe head restraint post.

According to another embodiment, a vehicle seat assembly is providedwith a seat back frame adapted to be mounted to a vehicle interior. Abracket is mounted to the seat back frame. At least one head restrainttube is mounted to the bracket and spaced apart from the seat back frameso that upon a rear vehicle impact, the bracket deforms as the at leastone head restraint tube is translated toward the seat back frame.

According to an even further embodiment, at least one head restraintpost is received within the at least one head restraint tube.

According to an even further embodiment, a head restraint is supportedupon the head restraint post.

According to another even further embodiment, the bracket is furtherprovided with a substrate. A projection extends from the substrate. Amounting surface is provided on the projection to mount the at least onehead restraint post.

According to an even further embodiment, the projection is tapered withan enlarged region at an upper distal end relative to a lower proximalend.

According to another embodiment, a vehicle seat assembly is providedwith a seat back frame adapted to be mounted to a vehicle interior. Abracket is formed from a sheet of steel, and is provided with asubstrate welded to the seat back frame. Two pairs of sidewalls extendfrom the substrate and are tapered with an enlarged region at an upperdistal end relative to a lower proximal end. A pair of support platesare each supported by one of the two pairs of sidewalls and spaced apartfrom the substrate to provide a mounting surface oriented at an anglerelative to the substrate facing an upright direction. A pair of spacedapart tubes are each welded to the bracket mounting surface of one ofthe pair of support plates. A pair of head restraint posts, are eachreceived in one of the pair of tubes. A head restraint is supported uponthe pair of head restraint posts, so that upon a rear vehicle impact,the bracket deforms as the pair of head restraint posts are translatedtoward the seat back frame.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation view of a vehicle seat assembly according toan embodiment;

FIG. 2 is an enlarged front perspective view of a seat back of thevehicle seat assembly of FIG. 1 according to an embodiment, illustratedpartially disassembled;

FIG. 3 is another enlarged front perspective view of the seat back ofthe vehicle seat assembly of FIG. 1 according to an embodiment,illustrated partially disassembled;

FIG. 4 is a front perspective view of another seat back of the vehicleseat assembly of FIG. 1 according an embodiment, illustrated partiallydisassembled; and

FIG. 5 is an enlarged partial section view taken along section line 5-5in FIG. 4.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the invention that may be embodied in variousand alternative forms. The figures are not necessarily to scale; somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for teaching one skilled in the art to variouslyemploy the present invention.

FIG. 1 illustrates a vehicle seat assembly 20 according to anembodiment. The vehicle seat assembly 20 may be a seat assembly in aland vehicle, such as an automobile. The vehicle seat assembly 20 mayalso be a seat assembly in an aircraft, watercraft, or the like. Thevehicle seat assembly 20 may be a multiple passenger seat assembly withmultiple seat subassemblies 22, 24. The seat assembly 20 may be locatedat any seating position within a vehicle. However, for the depicted seatassembly 20, the seat assembly 20 is a rear seating assembly 20.Additionally, the seat assembly 20 may include any number of seatsubassemblies 22, 24, of any size, such as a sixty percent seatsubassembly and a forty percent seat subassembly. However, the depictedembodiment includes two fifty percent seat subassemblies 22, 24.

The vehicle seat assembly 20 is illustrated in an upright seatingposition. Of course, the seat may be adjustable to non-seating, loadingor cargo positions. However, terms of spatial relation, such as above,below, upper, lower are terms to describe orientations of componentsrelative to other components, in an upright design or seating positionof the seat assembly 20. Likewise, terms such as forward and rearwardrefer to a forward seating position of an occupant in the upright seatassembly 20.

Each seat subassembly 22, 24 includes a seat bottom 26, 28 mounted to avehicle interior, such as a vehicle floor 30 of a vehicle body. Eachseat subassembly 22, 24 also includes a seat back 32, 34, which are alsomounted to the vehicle body. The seat backs 32, 34 may be mounteddirectly to the vehicle body, or may be pivotally connected to the seatbottoms 26, 28 to support the seat backs 32, 34 at an uprightarrangement relative to the seat bottoms 26, 28.

Each seat subassembly 22, 24 also includes a head restraint 36, 38supported above the corresponding seat back 32, 34. The head restraints36, 38 are each connected to the respective seat back 32, 34 by a pairof head restraint posts 40, 42. The head restraint posts 40, 42 areconnected to corresponding head restraints 36, 38 and seat backs 32, 34to support and orient the head restraints 36, 38 relative to the seatbacks 32, 34. As is known in the art, the head restraints 36, 38 may beadjustable relative to the head restraint posts 40, 42. As is also knownin the art, the posts 40, 42 may be adjustable relative to the seatbacks 32, 34.

The seat bottoms 26, 28, seat backs 32, 34, and the head restraints 36,38 each include an underlying frame, cushioning and trim, as is known inthe art. FIGS. 2 and 3 illustrate a seat back frame 44, 46 for the seatbacks 32, 34 with trim and cushioning removed. FIGS. 4 and 5 alsoillustrate the seat back frame 46 of the seat back 34. Each seat backframe 44, 46 includes a lower crossbar 48 (FIG. 4), a pair of sidemembers 50, 52 (FIGS. 2-5) interconnecting at terminal ends of the lowercrossbar 48, and extending upright to interconnect with an uppercrossbar 54 (FIGS. 2-5). Each seat back frame 44, 46 also includes asubstrate or platform 56 (FIGS. 2 and 3), 58 (FIGS. 2-5) spanning acrossthe crossbars 48, 54 and side members 50, 52 to enclose the seat back32, 34 and to separate the vehicle interior from a trunk or a cargocompartment. The components of the seat back frames 44, 46 may be formedfrom a structurally resilient material, such as a steel alloy, apolymeric material or the like.

It is common in the prior art to install a head restraint directly tothe seat back frame by welding. In a rear impact condition, the seatassembly is accelerated into the occupant, and consequently the seatback is accelerated into the back of the occupant, while the headrestraint is accelerated into the head of the occupant. In order tomanage energy of the impact condition upon the head of an occupant, aless stiff connection of the head restraints 36, 38 to seat back frames44, 46 is provided by the vehicle seat assembly 20.

With reference now to FIGS. 2-5, each vehicle seat subassembly 22, 24includes a deformable head restraint bracket 60. The brackets 60 areeach mounted to the seat back frame 44, 46. The brackets 60 support apair of head restraint tubes 62 (FIGS. 3-5). The pair of head restrainttubes 62 receive the head restraint posts 40, 42 to support the headrestraints 36, 38 upon the seat back 32, 34. An adjustment mechanism maybe provided in the tubes 62 to receive the posts 40, 42 for adjustmentof the posts 40, 42, and consequently adjustment of the head restraints36, 38 relative to the seat backs 22, 24.

The bracket 60 is designed to deform to manage energy in a rear impactcondition in order to increase deformation, and consequentlydeceleration to dissipate some of the impact forces of a rear impact.The bracket 60 is formed from stamped sheet steel with a substrate 64.The substrate 64 is displaced along the upper crossbar 54 of each seatback frame 44, 46. With reference to FIGS. 2, 3 and 5, the bracket 60also includes an offset region 66 at a lower proximal end of the bracket60. The offset region 66 is offset from the bracket substrate 64 toengage the seat frame platform 56, 58 of each seat back frame 44, 46.The offset region 66 is generally parallel to the bracket substrate 64and offset by a thickness of the upper crossbar 54.

Each seat back frame 44, 46 may include a plurality of alignment pins 68extending from the upper crossbar 54 and the seat back frame platform56, 58. Likewise, the bracket 60 includes a plurality of apertures 70 inthe bracket substrate 64 and the offset region 66 to receive thealignment pins 68. The alignment pins 68 align the brackets 60 relativeto the seat back frames 44, 46. The brackets 60 are fastened to the seatback frames 44, 46 by a suitable fastener, such as by welding.

Referring again to FIGS. 2-5, each bracket 60 includes a pair ofprojections 72 extending forward from the bracket substrate 64. Eachprojection 72 includes a pair of sidewalls 74 extending from thesubstrate 64, interconnected with a support plate 76 (FIGS. 2 and 5),which is spaced apart from the substrate 64. Each support plate 76provides a forward mounting surface for mounting one of the headrestraint tubes 62. According to an embodiment, the head restraint tubes62 are also formed form steel and are welded to the support plates 76 ofthe bracket 60.

Referring now to FIG. 5, the projections 72 may be formed so that thesupport plates 76 are provided at an upward facing acute angle relativeto the bracket substrates 64 by a taper in the sidewalls 74 which isenlarged toward an upper distal end of the projections 72. Upon a rearvehicle impact, the seat back 32, 34 of each vehicle seat subassembly22, 24 is accelerated into the back of the corresponding occupant.Likewise, the head restraint 36, 38 is also accelerated into a head ofthe corresponding occupant.

Upon a resultant force upon the head of the occupant reaching apredetermined design limit, the projections 72 of the bracket 60 deformelastically and then plastically to absorb and dissipate the impactforces to manage energy from the impact. During this deformation, thesidewalls 74 of the projections 72 compress, and then collapse todecelerate the head of the seated occupant, while the support plate 76translates toward the seat back frame 44, 46 and the angle between thesupport plate 76 and the bracket substrate 64 converges. A deformationlimit of the bracket 60 can be provided whereby the head restraint tubes62 collapse into indirect contact with the upper crossbar 54. Thepredetermined force for collapsing the bracket 60 can be optimized byselection of bracket materials, thickness of the sheet metal, size ofthe projection sidewalls 74, and other variables in the design of thebracket 60.

Referring now to FIGS. 4 and 5, the head restraint tubes 62 are weldedto the bracket 60 at an orientation to extend above the upper crossbar54. The vehicle seat subassembly 24 includes an additional translationlimit to prevent a full collapse of the projections 72. A pair oftranslation limit brackets 78 are mounted to the upper crossbar 54, eachin alignment with one of the head restraint tubes 62. Each limit bracket78 may be formed from steel, or any suitable structural material. Eachlimit bracket 78 includes a base 80 that is welded to a top surface ofthe upper crossbar 54 in alignment with one of the head restraint tubes62. The limit bracket base 80 extends forward and away from the uppercrossbar 54. Each limit bracket 78 also includes a contact portion 82extending at an upright angle from the limit bracket base 80 to providean area contact with the head restraint tube 62 to distribute the forcesfrom the impact.

The deformation limit also includes a pair of steel contact targetplates 84 that are welded onto the head restraint tubes 62 in alignmentwith the limit bracket contact portions 82. The limit bracket contactportions 82 and the contact target plates 84 are spaced apart apredetermined distance associated with a designed deformation of theprojections 72. The limit bracket contact portions 82 are also angledrelative to the contact target plates 84 by an angle α. The angle α issized so that upon the deformation of the tapered projections 72, anarea contact is provided with the impact of the limit bracket contactportions 82 and the contact target plates 84.

The contact target plates 84 add structural reinforcement to the headrestraint tubes 62 at a region of force distribution in order tominimize distribution of the loading to an internal sleeve that receivesthe head restraint post 40, 42.

The deformation limit of the limit brackets 78 and the contact targetplates 84 can be designed to limit deformation of the bracket 60 to adesired limit, such as an angular range of translation, a predeterminedforce, elastic deformation, elastic and plastic deformation, or anyapplicable design specification. Additionally, by controlling thedeformation to a particular region of the seatback subassemblies 22, 24,the seatback subassemblies 22, 24 can be designed relatively compact.

While various embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. A vehicle seat assembly comprising: a seat backframe adapted to be mounted to a vehicle interior; a bracket mounted tothe seat back frame; and at least one head restraint post mounted to thebracket and spaced apart from the seat back frame so that upon a rearvehicle impact, the bracket deforms as the at least one head restraintpost is translated toward the seat back frame.
 2. The vehicle seatassembly of claim 1 wherein the bracket further comprises: a substrate;a projection extending from the substrate; and a mounting surface on theprojection to mount the at least one head restraint post.
 3. The vehicleseat assembly of claim 2 wherein the projection is tapered with anenlarged region at an upper distal end relative to a lower proximal end.4. The vehicle seat assembly of claim 2 wherein the projection furthercomprises a pair of sidewalls extending from the substrate.
 5. Thevehicle seat assembly of claim 4 wherein the projection furthercomprises a support plate supported by the pair of sidewalls and spacedapart from the substrate to provide the mounting surface.
 6. The vehicleseat assembly of claim 5 wherein the support plate is not parallel withthe substrate.
 7. The vehicle seat assembly of claim 6 wherein thesupport plate is oriented at an angle relative to the substrate.
 8. Thevehicle seat assembly of claim 7 wherein the angle faces an uprightdirection.
 9. The vehicle seat assembly of claim 2 wherein the bracketis formed from a sheet of material.
 10. The vehicle seat assembly ofclaim 9 wherein the bracket is formed from sheet steel.
 11. The vehicleseat assembly of claim 1 further comprising at least one tube mounted tothe bracket and sized to receive the at least one head restraint post.12. The vehicle seat assembly of claim 11 wherein the bracket is weldedto the seat back frame.
 13. The vehicle seat assembly of claim 12wherein the at least one tube is welded to the bracket.
 14. The vehicleseat assembly of claim 1 further comprising a head restraint supportedupon the head restraint post.
 15. A vehicle seat assembly comprising: aseat back frame adapted to be mounted to a vehicle interior; a bracketmounted to the seat back frame; and at least one head restraint tubemounted to the bracket and spaced apart from the seat back frame so thatupon a rear vehicle impact, the bracket deforms as the at least one headrestraint tube is translated toward the seat back frame.
 16. The vehicleseat assembly of claim 15 further comprising at least one head restraintpost received within the at least one head restraint tube.
 17. Thevehicle seat assembly of claim 16 further comprising a head restraintsupported upon the head restraint post.
 18. The vehicle seat assembly ofclaim 16 wherein the bracket further comprises: a substrate; aprojection extending from the substrate; and a mounting surface on theprojection to mount the at least one head restraint post.
 19. Thevehicle seat assembly of claim 18 wherein the projection is tapered withan enlarged region at an upper distal end relative to a lower proximalend.
 20. A vehicle seat assembly comprising: a seat back frame adaptedto be mounted to a vehicle interior; a bracket formed from a sheet ofsteel, and comprising: a substrate welded to the seat back frame, twopairs of sidewalls extending from the substrate and tapered with anenlarged region at an upper distal end relative to a lower proximal end,and a pair of support plates, each supported by one of the two pairs ofsidewalls and spaced apart from the substrate to provide a mountingsurface oriented at an angle relative to the substrate facing an uprightdirection; a pair of spaced apart tubes each welded to the bracketmounting surface of one of the pair of support plates; a pair of headrestraint posts, each received in one of the pair of tubes; and a headrestraint supported upon the pair of head restraint posts, so that upona rear vehicle impact, the bracket deforms as the pair of head restraintposts are translated toward the seat back frame.